Better denaturant than SDS?

Hi netters,
I want to stop enzymatic reaction without using heat. I work under in situ
condition with raw material. Heating extract a lot of unwanted stuff. I
used SDS as denaturing agent but it's a bit too foamy. Any suggestion on
better denaturing agent? Any other idea on stopping enzymatic reaction
under in situ conditions with raw material?
E-mail me your answers.
Thank's.
Christian Belanger
c_belanger2 at qc.dfo.ca